Propeller hub



April 21, 1931. F W CALDWELL 1,801,486 PROPELLER HUB v Filed Jan. 18,19.26

INVENT Fea/wr W awt-A Patented Apr. 21, 1931 Y ,UNITED sTATEs PATENTOFFICE FRANK W. CALDWELL, .OP DAYTON, OHIO, AssIGNOR, BY unsNnASSIGNMENTS, To THE HAMILTON STANDARD PDOPELLER. CORPORATION, -ACORPORATION OP PENN- sYLvANIA PROPELLER HUB Application ined January 1s,192s. serial No. 82,062.

This invention relates to propellers and pair of bolts 13 on each sideof the axis of roe primary object is to provide a constructation of thepropeller to the second hemition which will be easily machined andreadicylindrical mating portion 14 which is rigidly assembled, and whichwill provide for vthe ly connected to or integral with thecrankadjustable pitch of the blades. i -shaft 15 of the en ine whichdrives the pro- 55 further Object is a provision of a split peller. Apair of anges-16 extend outwardly u member divided into two halves inwhich from lthe split hub member, and are spaced the bases vof theblades are clamped; these apart the exact distance of the width of theblades being held in position by means of umembers 12 and 14, so that`the hub member a pair of clamp rings. The split hub memand the bladesmounted therein are accurately so ber itself is held within a splitholder, a part positioned properly with symmetrical refo which isrigidly connected to or integral erence to the axis of rotation. withthe crankshaft of the engine which While Ihave herein shown my inventionin vdrives the propeller. .The blades arene'- the form of a metalairplane propeller, it strained against outward movement within will beobvious that various other forms of 65 the hub member by the provisionof a ange the same may be employed. Furthermore, it or anges on thebases of the blades which will be obvious that, if it should be sodesired, abut against corresponding flange grooves in the two blades maybe made integral. I am the split hub member. aware that various othermodifications may 20 Further objects and advantages of my -inbemadewithin the scope of my invention, 70 vention will be more fully setforth in the and do not intend to be limited to thev recise vollowingdescription, inthe claims and in construction which has beenchosen erein the drawings in which` for illustration. y'

Fig. 1 isa side elevation, partly in section I claimz' c of ,an aircraftpropeller in accordance with 1. In an aircraft propeller, a split hub 76my invention, and ,A member of circular' transverse cross section Fig.,2 is a section on line 2 2 of Fig. 1. throughout comprising oppositehalves, a Y Referrin lmore particularly to the drawpair of adjustableblades having bases mountz ings by reference numerals, the two blades eddirectly in said member, a pairof clamp l and 2 are mounted within thesplit hub rings, one at each end of said hub member to so member formedof halves 3 and 4. The inner hold the blades from turning. and othermeans end of each of the blades is provided with for holding theopposite halves of lsaid hub two anges 5 and 6 whic are neatly mamembertogether.

' chined, so that they will bear against corn an aircraft propeller, asplit hub responding flange grooves 7 and 8, respecmember of circulartransverse cross section 85 tively, provided in the hub member. The'throughout, comprising opposite halves, a blades are thus restrainedagainst outward pair of blades having bases mounted ydirectorlongitudinal movement in the hub memly in said member for adjustmentangularly ber. c therewith, a flange on the basc of .each blade,

40 Each blade is held -withinthe hub memcooperating with a correspondingflange in 90 ber, so as to be mounted fixedly `therein by said hubmember, a groove in the hub memmeans of a clamp ring 9, having'a singleber to restrain the blade against outward bolt 10 which draws thetwo endears '11 tomovement, a pair of clamp rings one at each gether, to thustake up slightly the space at end of saii hub member to 'hold the blades15'12 between the two halves of the hub memfrom turning therein, andother means for 95.

r and prevent rotation of the blades holding-the opposite halves of saidhub memherein. Y f ber together.

The hub member, itself, is held in a' two 3. In an aircraft propeller, a'split hub piece split holder formed of'a hemicylindrimember of circulartransverse cross section cal cpp 12 which is clampe by means of athroughout, a. pair of blades having bases 100 2 1,301,486 mounteddirectl in said member, dan es on the bases of the lades,` cooperatingwit i co .i responding ange grooves 1n the hub member to restrain thebla es against outward movee at each en of said hub member to hold thebladesfromV turning in the hub member, a split holder encircling acentral portion of said hub member, and means for elampin g the parts ofthe hold- ,0 er together.

4. In an aircraft propeller, a split hub member, a pairof blades havingbases mounted directly in said member, means on the base of each blade,cooperating with complementary means in the hub member to restrain theblade against outward movement, a pair o clamp rings one at each endoffsaid hub member to hold the bladestherein, a s lit holder encirclingthe middle portiono said. hub

member, and means for clamping the parts o the holder together. v

l5. In an aircraft propeller, a` split hub member, a pair of bladeshavin ,bases Y mounted directl in said member, a ange on the base of eacblade, cooperating with a corresponding fiange roove in the hub mem-iber to restrain theyk lade against outward movement, a pair of clamprings one at each end of saidhub member to hold the blades ao therein, asplit holder encircling said ub member, and means for clamping the partsof the holder togetheryone of the (parts of said holder being rigidlyconnecte propeller drive sha t.

6. In a pro eller of the class described, a`Y split hub mem er, a pairof adjustable blades having bases mounted directly in sai ub member,clamping means at each end ofsaid hub member to hold the blades therein,cen- '40 trally disposed hemi-cylindrical clamping means surroundingsaid hub member an a driving shaft inte gral with a hemi-cylindrical`part of said clamping means. i

7. Ina propeller of the class described, a 46 split hub member, a pairof adjustable blades havingV bases mounted directly in said hub member,clamping means at each end of said hub member to hold the bladestherein,.cen trally disposedsplit hemi-oylindricai clamp# 50 ing means'surrounding said member, an a driving shaft integral with ahemi-cylindrical part of Ysaid centrally disposed clamping means. v y

` In testimony wheeofI affix mv signature.

s FRANK W. CALDWELL.

` 'nos

